The present invention relates to freeze-thaw stable stoneware tile having water absorption of not more than about 10%, and to a process for production thereof.
In order to prevent tiles such as indoor tile from freeze-thaw damage, hitherto there has been used a porcelain body for the tile having water absorption of less than 0.5% or 1%, or employed water-repellent treatment on a tile body having higher water absorption. Production of the porcelain tile requires a firing temperature higher than the case of the stoneware tile. As a result, deformation of the resulting tile bodies and some unevenness on glazed tile surfaces have resulted from the softening of the tile bodies due to such high firing temperature. Also, porcelain tile can not be fired in such a fashion that a multiplicity of tile bodies are arranged vertically in saggers (i.e. firing vessels). Moreover, a larger amount of fuel or electric power is needed for production of such porcelain tile bodies. On the other hand, the water-repellent treatment requires an additional apparatus therefor. There is also a problem of the durability of such water-repellent effects.